Production of slivers of artificial fibers



June 21, 1949. w, 3, ABBOTT, JR 2,473,499

PRODUCTION OF SLIVERS OF ARTIFICIAL FIBERS Filed April 30, 1946 memr 11 m Gdqf J7: MW)

Patented June 21, 1949 UNITED S TATEJS PRODUCTION OF. SLIVE B S QE ARTI EIGIA FIBERS William G. Abbott, Jr., Milford, NQIH. Application April '30, 1946,,SeriaLNO. 66,172

,lapped and staggered longitudinally of the s ver- Mya plicatiton Serial No. 506,664, filed October 18, 1943, patented as No. 2,399,191, dated April 30, 1946, describes the feeding to the plu- .rality of orifices of an extrusion nozzle a composite of filament-forming material and another, non-filament-forming, material, with thosematerials,sodisposed that,-bodies of each are presented to the individual, orifices at frequent intervalsthebodies of non-filament-forming material Jfillingtheorifi-ce cross-section and thereby temporarily excluding the filament-forming material ,frompassage through the orifice. By separating the non-filament-forming material from the fila- ,,ment,-forming materialafter extrusion of the sliver, the resulting sliver comprises overlapped andjlongitudinally staggered staple length filaments adapted for the spinning processeswith little if any further rearrangement of thestaple "filaments.

"The present invention aims toimprove ,upon the process of said application, SerialNo. 506,664,

by avoiding the necessity for inclusion of a non- .filament iorming material as an element of the composite which is extruded, and also aims to improve over the process of said application by providing av more expeditious way of producing a continuous phase and another filament-forming material in a dispersed phase, both of these materials being in a fiowable condition and being immiscible with each other so that each retains its separate identity. In practice this condition is bestsecured by adjusting the relative fluidity of the filament-forming materials before putting them together, so that one of these materials is suiiiciently, less fluid than the other material so :asto exist in the form of particles dispersed ,through the said other material. Stability of the dispersion is further promoted by use of dispersed ;.Dar ticles. havinga .difierent surface tension from that of the continuous material.

The drawingis a diagrammatic viewshowinga dispersion of tbodieszot one filament-forming ma- 1 terial inanother filament-forming material passs t ou an e t u on oz leinto a h en bath, producing a ,S1iver of staple lengths of. each ofathe two kinds .of, filament-ior ning material, the diametersof these staplelengthsbeing greaty. xas eratedin o derto permit. the two kind of'fibers to be distinguished inr.,t h drawing.

The relative proportions of the filament iorms ate ial may be adjustcdlwithina .Wide range, and thejproportion of one ,tothe other will ,govern the H, proportion of, one ,kind of filament to the other kindfof filament in, the extrudedsliver.

A wide variety ,of cgmbinations ;of, filamentforming materials, vmay ,be employed. For int e onenlamente o mins. mate l m y be a protein such. as the product made iromcasein, which is e truded .to .makath fi ergknow commercially as fAralac," -and ,the.;other filamentforming material may, be; a cellulose basematcrial such as viscose. Both of ,thesematerials may be prepared in alkaline solution in a plastic-form. fI-helfilament iorming. naterial which is selected to constitute the dispersed phase of ,the composite ,will, asindicated above, be prepared with a sufiiciently less fluid consistency seas to exist in the form. of particles,dis ersedthrough the other, more fluid, material.

Various means for adjusting the ,fluidity of either v of the filament forming, materials are available. The fluidity-reducingpotions of coasulantsan hardenin ent ap op te to the ,rarious fi arnenteiqrminamats a s a t emselves =w 11 kn wn endear be employed in the preparation of the material that .is to. form the dispersed ,phase ,to reduce the c flu t of this material relative tmthei luidityof, the othenmaterial. Reduction oflfiuidityto su-ch point asto preventfiow is, oicoprsato bep ioided, sinceeven the less fluid material should, as ,indicated above, ,stillib eplastic in, ord er to how through the orificesofthe nozzle.

Dif ren e in sur a e tens n resthe tw ases can e be enhanced ba-known ans 1Qh ,as emulsification; ,such; for instance a g incorporating ,small quantities ,of .a water-immiscible oil .inthe material that is intended to form,rthe dispersed phase, thereby to increase surface. tension pf particles of this ,material.

The length. of time in yvl ieh the two distinct phases arearequired to .coexist in the material to be extruded, of course depends upon the time elapsing between dispersion-pf thematerial of one phasein the material of theotherphase and passage of :the dispersed p i'rticlessthrough the orifice of theextrusipngnozzle. Itis obvious that vthis,ti-rmamay be Quite-short.

The composite of the filament-forming materials is continuously fed to the plurality of adjacent orifices of an extrusion nozzle with the materials substantially uniformly disposed throughout the composite, and in passing through the individual orifices the particles of the less fluid filament-forming material at frequent intervals fill an individual orifice cross-section and temporarily exclude the other material, thereby alternating the materials that flow from a given orifice and staggering the staple filamentswhich emerge from the group of orifices of the nozzle. Thus in the accompanying drawing dispersed particles of, for instance, casein, indicated at C and shown in black, fill the cross sections of certain of the individual orifices of a spinneret I l to the exclusion of the continuous phase filament-forming material, for instance viscose, indicated at V and shown as colorless, while at other individual orifices the continuous phase filament-forming material fills the cross sections of the orifices to the exclusion of the dispersed particles of casein. Thus separate staple lengths of casein SC (shown in black) and viscose SV (shown as colorless) are simultaneously produced, and are staggered and overlapped in the resulting sliver.

The extruded sliver emerging from the nozzle may then be subjected to a suitable hardening step, for instance by passing it into a bath l2 of sulphuric acid and formaldehyde adapted llJO harden both materials of the sliver.

Any tendency of the filament-forming materials to weld or stick together end to end during extrusion is obviated by the difierent surface tensions of the materials and/or by providing a gentle pull on the filaments as by flow of the fiuid of the hardening bath along the filaments in their direction of departure from the nozzle.

The necessity for passage of inert or non-filament-forming material through the extrusion orifice as an interrupting agent is thus avoided, and a sliver consisting of a blend of filaments is expeditiously produced without the usual fibermixing processes.

Iclaim:

1. Method of forming a sliver of artificial fiber which comprises forming a composite comprising a filament-forming material in a continuous phase and another filament-forming material in a dispersed phase, both of said materials being in a fiowable condition and being immiscible with each other so that each retains its separate identity, continuously feeding said composite to a plurality of adjacent orifices adapted to extrude the plurality of filaments which together constitute a sliver, said materials being so disposed substantially uniformly throughout the composite, as to present bodies of each material to the individual orifices at frequent intervals, such :bodies of each filament-forming material filling the orifice cross section to the temporary exclusion of the other filament-forming material, thereby forming pieces of filament of staple length to produce a sliver from the several orifices comprising overlapped and longitudinally staggered pieces of both filament-forming materials.

2. Method of forming a sliver of artificial fiber in which a composite of fiowable materials is fed through a plurality of adjacent orifices, and bodies of each material interrupt passage of the other material through the individual orifices, characterized in that both said materials comprise filament-forming materials, one said material being in continuous phase and the other said material being in dispersed phase so that passage of each such body through an orifice forms such body into a staple length filament, and after passage through said orifices, both of said materials are subjected to hardening, to form a sliver.

3. Method of forming a sliver of artificial fiber in which a composite of fiowable materials is fed through a plurality of adjacent orifices, and bodies of each material interrupt passage of the other material through the individual orifices, characterized in that both said materials comprise filament-forming materials, and are in alkaline condition, one said material being in continuous phase and the other said material bein in dispersed phase, so that passage of each such body through an orifice forms such body into a staple length filament and after passage through said orifices, both of said materials are subjected to hardening in an acidic bath to form a sliver.

4. Method of forming a sliver of artificial fiber which comprises forming a composite comprising a filament-forming material and another filament-forming material, both of said materials being fiowable and one of said materials being sufiiciently less fiuid than the other material so as to exist in the form of particles dispersed through the said other material, and continuously feeding said composite to a plurality of adjacent orifices adapted to extrude the plurality of filaments which together constitute a sliver, said particles of the less fluid filament-forming material at frequent intervals filling the individual orifice cross section to the temporary exclusion of the other material, thereby forming pieces of filament of staple length to produce a sliver from the several orifices comprising overlapped and longitudinally staggered pieces of both filament-forming materials.

5. Method of forming a sliver of artificial fiber which comprises forming a composite comprising a filament-forming material and another filament-forming material, both of said materials being in alkaline condition and being fiowable and one of said materials being sufliciently less fiuid than the other material so as to exist in the form of particles dispersed through the said other material, continuously feeding said composite to a plurality of adjacent orifices adapted to extrude the plurality of filaments which together constitute a sliver, said particles of the less fiuid filament-forming material at frequent intervals filling the individual orifice cross section to the temporary exclusion of the other ma terial, thereby forming pieces of filament of staple length to produce a sliver from the several orifices comprising overlapped and longitudinally staggered pieces of both filament-forming materials, and hardening the resulting filaments of the sliver by acid.

6. Method of forming a sliver of artificial fiber "which comprises forming a composite comprising a protein filament-forming material and a cellulose base filament-forming material, both of said materials being in alkaline condition and being fiowable and one of said materials bein sufiiciently less fiuid than the other material .so as to exist in the form of particles dispersed through the said other material, continuously :feeding said composite to a plurality of adjacent orifices adapted to extrude the plurality of filaments which together constitute a sliver, said particles of the less fluid filament-forming material at frequent intervals filling the individual orifice cross section to the temporary exclusion of the other material, thereby forming pieces of filament of staple length to produce a sliver from the several orifices comprising,overlapped and longitudinally staggered pieces of both filamentforming materials, and hardening the resulting filaments of the sliver.

WILLIAM G. ABBOTT, JR,

REFERENCES CITED The following references are of record in the file of this patent:

Number Number UNITED STATES PATENTS Name Date Pazsiczky et a1. Oct. 19, 1943 Thinius Apr. 25, 1944 FOREIGN PATENTS Country Date Great Britain Apr. 21, 1938 

